Dual-stack mode favouring IPv4 incorrectly

[Phil2021]

Hi (no wonder this forum is quiet as messages just get flagged as SPAM by Akismet, not sure how this can be considered SPAM, so its a rubbish system, maybe adding this as extra text works! Edit: Yes adding this text allows it through.)

I've found a bug that means when dual-stack is selected, even though IPv6 is set as preferred, the phone incorrectly favours IPv4 and will not use IPv6.

Firmware version: 77.85.0.25

Setting W60B for IPv6 only, all works correctly and the phone registers using IPv6.

Setting it to IPv4 & IPv6 (so dual stack) and setting preference to IPv6 never results in the registration over IPv6 but it always defaults to IPv4. I can enter the IPv6 address as the SIP server host (rather than the domain) and it will connect via IPv6, so IPv6 is functioning in dual-stack mode. The SIP domain DNS correctly brings back IPv6 addresses, which is why it works under IPv6 single stack but on dual-stack it favours IPv4 addresses over IPv6 addresses and this incorrect when the preference is for IPv6.

I've tried: Disabled and re-enabled the SIP account to see if it then uses IPv6 which it doesn't, this was to rule out that on the reboot the phone was favouring IPv4 as that network simply came up first, this isn't the case.

Many thanks.

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So found the answer doing a search in the forum. Someone else fell over this bug in 2017 on a different model, seems some configuration setting needs changing that isn't in the UI.

http://forum.yealink.com/forum/showthrea...light=ipv6

I exported the configuration file, added the setting below, reimported and rebooted and now in dual-stack it favours IPv6.

Code:

account.1.sip_server_mode = 1

Surely 5 years on this should be resolved by now?